Gas turbine engines commonly have containment envelopes or structures. The containment envelopes or structures are rings that surround rotors in the gas turbine engine, so as to contain released blade fragments, to prevent such fragments from escaping the gas turbine engine. In providing such containment structures, it is desirable to minimize the size of the containment structures, while minimizing any impact on containment capability of the containment structure and while controlling rotor tip clearance through the support of the shroud segments.